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61.
The effect of different high pressure treatments on K-value, total plate count, enterobacteriaceae and organoleptic characteristics of yellowfin tuna chunks packed in ethyl vinyl alcohol (EVOH) films during chill storage (2 ± 1 °C) was studied. 50 g of fresh tuna chunks were placed in EVOH multilayer film pouches and vacuum packed for the trials. Tuna chunks were subjected to 100, 200 and 300 MPa for 5 min at 25 °C. Control was vacuum packed tuna without pressure treatment. K value, microbiological analysis and sensory characteristics were evaluated at periodic intervals. The K-value of the samples was found to decrease with increase in pressure when compared to the control. However, K-value was found to increase in all the samples during storage. Higher pressure treatment showed a decrease in the total plate count in the samples which increased during the storage. The Enterobacteriaceae decreased with increasing pressure and during storage. Control samples were sensorally acceptable up to 20 days of storage. During the storage period of 30 days 200 MPa treated tuna chunks was found most acceptable based on above parameters.

Industrial relevance

High pressure processing is a non thermal processing method which has wide applications in food industry. Fish is a highly perishable commodity and it has a limited shelf life in chill conditions. High pressure treatment has been found to effectively extend the shelf life of various products. In this study, HPP has been effectively demonstrated for enhancing the storage period of tuna at low temperature. Such studies can be commercially applied by fish processing industries to preserve the valuable catch and can enhance the marketing potential of tuna.  相似文献   
62.
Summary Solutions for the equations of motion of an incompressible second-grade fluid are obtained by employing hodograph-transformation methods. By introducing a suitable Legendre-transform function the basic equations are recast in terms of this function, and the conditions which this function should satisfy are stated. Several illustrations of the method are considered and the results for stream-lines, velocities and pressure distribution are compared with the corresponding results for viscous fluids.  相似文献   
63.
Sodium meta silicate gel is proposed as a novel coupling medium with a better coupling and a lesser dielectric loss than the conventionally used media. Dielectric constants between 8 and 20 exhibited for various relative density and pH, makes the material in perfect match with that of the various tissues. It is also useful as a phantom model material in microwave medical imaging.  相似文献   
64.
Hodograph transformation is employed to obtain a partial differential equation of second order, which is exploited to obtain solutions for plane viscous incompressible flows with orthogonal magnetic and velocity fields. This approach is illustrated through three examples.  相似文献   
65.
We have demonstrated in our previous studies that ventral subicular lesion induces neurodegeneration of the hippocampus and produces cognitive impairment in rats. In the present study, the efficacy of transplanted green fluorescent protein (GFP)-labeled hippocampal cell line (H3-GFP) cells in establishing functional recovery in ventral subicular lesioned rats has been evaluated. The survival of H3-GFP transplants and their ability to express trophic factors in vivo were also investigated. Adult male Wistar rats were subjected to selective lesioning of ventral subiculum and were transplanted with H3-GFP cells into the cornu ammonis 1 (CA1) hippocampus. The transplants settled mainly in the dentate gyrus and expressed neurotrophic factors, brain-derived neurotrophic factor (BDNF), and basic fibroblast growth factor (bFGF). The ventral subicular lesioned (VSL) rats with H3-GFP transplants showed enhanced expression of BDNF in the hippocampus and performed well in eight-arm radial maze and Morris water maze tasks. The VSL rats without hippocampal transplants continued to show cognitive impairment in task learning. The present study demonstrated the H3-GFP transplants mediated recovery of cognitive functions in VSL rats. Our study supports the notion of graft meditated host regeneration and functional recovery through trophic support, although these mechanisms require further investigation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
66.
Abstract

Neodymium vanadate with concentration of gadolinium as 3% and 5% having general formulae GdxNd1-xVO4 where x?=?0.03 and 0.05 was prepared by chemical route technique. The effect of concentration of gadolinium on the structural, optical and spectroscopic properties was explained by various characterization techniques. Powder X-ray diffraction study suggests tetragonal zircon structure; various parameters such as crystallite size, volume and X-ray density were calculated. A change in morphology with the change in concentration of gadolinium was observed through scanning electron microscopy. Ultraviolet absorption spectroscopy shows various transitions from ground state to various excited state within 4f shell, and variation in the optical band gap calculated by Tauc plot is due to the incorporation of Gd3+ ions.  相似文献   
67.
A major problem in networking has always been energy consumption. Battery life is one parameter which could help improve Energy Efficiency. Existing research on wireless networking stresses on reducing signaling messages or time required for data transfer for addressing energy consumption issues. Routing or Forwarding packets in a network between the network elements like routers, switches, wireless access points, etc., is complex in conventional networks. With the advent of Software Defined Networking (SDN) for 5G network architectures, the distributed networking has embarked onto centralized networking, wherein the SDN Controller is responsible for decision making. The controller pushes its decision onto the network elements with the help of a control plane protocol termed OpenFlow. Decentralized networks have been largely in use because of their ease in physical and logically setting the administrative hierarchies. The centralized controller deals with the policy funding and the protocols used for routing procedures are designated by the decentralized controller. Ambience Awake is a location centered routing protocol deployed in the 5G network architecture with OpenFlow model. The Ambience Awake mechanism relies on the power consumption of the network elements during the packet transmission for unicast and multicast scenarios. The signalling load and the routing overhead witnessed an improvement of 30% during the routing procedure. The proposed routing mechanism run on the top of the decentralized SDN controller proves to be 19.59% more efficient than the existing routing solutions.  相似文献   
68.
Chemo-resistance has pushed cancer treatment to the boundary of failure.This challenge has encouraged scientists to look for nanotechnological solutions.In this study,we have taken this goal one step further without depending on chemotherapy.Specifically,hybrid metal,polymer,and lipid nanoparticles that formed an IR780-a photosensitizer and Zinc copper oxide incorporated nanoparticle(ZCNP)nanoparti-cles were utilized in a combined photothermal and photodynamic therapy.Through the mediation of triphenylphosphonium(TPP)as a mitochondria-targeting moiety,TPP-conjugated polymer-lipid hybrid nanoparticles containing ZCNP/IR-780 significantly enhanced cellular uptake by cancer cells and selec-tively targeted the mitochondria,which improved the induction of apoptosis.In tumor-bearing mice,the nanoparticles were detected predominantly in tumors rather than in the other principle organs,which did not show notable signs of toxicity.Both in vitro and in vivo results demonstrated a great improvement in photothermal and photodynamic efficacy in combination when compared to either one individually,and a significant inhibition of tumor growth was observed with the combined therapies.In summary,this study describes an effective mitochondria-targeting nanocarrier for the treatment of cancer using combined photothermal and photodynamic therapies.  相似文献   
69.
Isradipine (ISR) is a potent calcium channel blocker with low oral bioavailability due to low aqueous solubility, extensive first-pass metabolism and P-glycoprotein (P-gp)-mediated efflux transport. In the present investigation, an attempt was made to develop isradipine-loaded self-nano emulsifying powders (SNEP) for improved oral delivery. The liquid self-nano emulsifying formulations (L-SNEF/SNEF) of isradipine were developed using vehicles with highest drug solubility, i.e. Labrafil® M 2125 CS as oil phase, Capmul® MCM L8 and Cremophor® EL as surfactant/co-surfactant mixture. The developed formulations revealed desirable characteristics of self-emulsifying system such as nano-size globules ranging from 32.7 to 40.2?nm, rapid emulsification (around 60?s), thermodynamic stability and robustness to dilution. The optimized stable self-nano emulsifying formulation (SNEF2) was transformed into SNEP using Neusilin US2 (SNEPN) as adsorbent inert carrier, which exhibited similar characteristics of liquid SNEF. The solid state characterization of SNEPN by Fourier transform infrared spectroscopy, differential scanning calorimetry, powder X-ray diffraction and scanning electron microscopic studies shown transformation of crystalline drug into amorphous form or molecular state without any chemical interaction. The in vitro dissolution of SNEPN compared to pure drug was indicated by 18-fold increased drug release within 5?min. In vivo pharmacokinetic studies in Wistar rats showed significant improvement of oral bioavailability of isradipine from SNEPN with 3- and 2.5-fold increments in peak drug concentration (Cmax), area under curve (AUC0–∞) compared to pure isradipine. In conclusion, these results signify the improved oral delivery of isradipine from developed SNEP.  相似文献   
70.
We present the spectral and nonlinear optical properties of ZnO-SiO2 nanocomposites prepared by colloidal chemical synthesis. Obvious enhancement of ultraviolet (UV) emission of the samples is observed, and the strongest UV emission of a typical ZnO-SiO2 nanocomposite is over three times stronger than that of pure ZnO. The nonlinearity of the silica colloid is low, and its nonlinear response can be improved by making composites with ZnO. These nanocomposites show self-defocusing nonlinearity and good nonlinear absorption behavior. The observed nonlinear absorption is explained through two photon absorption followed by weak free carrier absorption and nonlinear scattering. The nonlinear refractive index and the nonlinear absorption increase with increasing ZnO volume fraction and can be attributed to the enhancement of exciton oscillator strength. ZnO-SiO2 is a potential nanocomposite material for the UV light emission and for the development of nonlinear optical devices with a relatively small limiting threshold.  相似文献   
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